Go a little every day fundamentals of grammar and language --Go language primitive data types

A, Go language basic grammar

Part I talked about the Go language to explain the basic structures of the language related to Go, the measure would go to talk about the basic grammar of the language. Go language program by a plurality of markers, for example: keywords, identifiers, constants, symbols, strings.

Line separator - row represents the end of a sentence, without having to write ";." Of course, you can write multiple statements on one line, and use ";" No distinction, but not recommended to write code development.

Comment on this article is not to say.

Identifier

If the variable is the first hurdle to get started shell, it can be said, the identifier is the first threshold development language.

Identifier, Officially explanation: for naming the variables, type of program entities. It includes an identifier of the features: a fact or a plurality of letters (A ~ Z and a ~ z) numbers (0 to 9), _ underlined sequence composition, but the first character must be a letter underlining not huo is a number.

My personal understanding: identifier can be understood as the language already booked good words (keywords) and (development programmer or user) defined by the value of their own programmers (above mentioned entities).

Keyword

Here a list of what can be analogy shell in time, case, if, default, etc.

25 keywords and reserved words:


break	default	func	interface	select
case	defer	go	map	struct
chan	else	goto	package	switch
const	fallthrough	if	range	type
continue	for	import	return	where

Go language as well as 36 predefined identifiers


append	bool	byte	cap	close	complex	complex64	complex128	uint16
copy	false	float32	float64	imag	int	int8	int16	uint32
int32	int64	iota	only	make	new	nil	panic	uint64
print	println	real	recover	string	true	uint	uint8	unitptr

go by the general language program keywords, constants, variables, operators, type, and functions; may be used to program these delimiters: parentheses (), brackets [] and braces {}; programs may be used to these punctuation: ,,,;,: and ....

Two, Go language data types

In the Go language, the data type used to declare functions and variables. Appears to the data type of data into different memory sizes required data, programming time needed when it is large data need to apply large memory, can take advantage of the memory.

Go language data types are: bool type, numeric type, string type, derived type

Boolean

Boolean values can only be constants true or false. A simple example: var b bool = true.

Numeric

Into integer, floating point, and the corresponding float int

Go language support integer and floating point numbers, and native support complex, wherein the position calculation using complement

Integer

1, uint family (unsigned int)

8-- ~ range: 0 ~ 255
16-- ~ range: 0 to 65535
32-- ~ range: 0 to 2 ^ 32-1
64-- ~ range: 0 to 2 ^ 64-1

2, int family (signed integer)

8-- ~ range: -127 to 128
16-- ~ range: -32768 to 32767
32-- ~ range: -2 ^ 31 to 2 ^ 31-1
64-- ~ range: -2 ^ 63 to 2 ^ 63-1

Float

float32 - IEEE-754 32-bit floating point number

float64 - IEEE-754 64-bit floating point number

complex64--32 bit real and imaginary

complex128--64 bit real and imaginary

Other types of digital

byte-- with similar uint8

rune-- with similar int32

uintptr-- unsigned integer, pointer storage